[clang] [llvm] [AMDGPU] Use `bf16` instead of `i16` for bfloat (PR #80908)

[Stanislav Mekhanoshin via cfe-commits]

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@@ -0,0 +1,8 @@
+// RUN: llvm-mc -arch=amdgcn -mcpu=gfx1100 -show-encoding %s | FileCheck %s
+// RUN: llvm-mc -arch=amdgcn -mcpu=gfx1200 -show-encoding %s | FileCheck %s
+
+v_dot2_bf16_bf16 v5, v1, v2, 100.0
+// CHECK: v_dot2_bf16_bf16 v5, v1, v2, 0x42c8 ; encoding: [0x05,0x00,0x67,0xd6,0x01,0x05,0xfe,0x03,0xc8,0x42,0x00,0x00]
+
+v_dot2_bf16_bf16 v5, v1, v2, 1.0
+// CHECK: v_dot2_bf16_bf16 v5, v1, v2, 1.0 ; encoding: [0x05,0x00,0x67,0xd6,0x01,0x05,0xca,0x03]
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rampitec wrote:

Wow! Yeah, it's another ticket. Looks like a can of worms.
Add at least 'v_dot2_bf16_bf16 v2, v0, 1.0, v2', this one works.

https://github.com/llvm/llvm-project/pull/80908